You do not have to be stressful. Stress is work of the devil. When there is stress, the devil has poked its nose.
The devil does not go against it. If there is a tendency, he makes it bigger to cause much distress and mislead you.
For example, he forces the sensitive one to become hypersensitive. When you are willing to repent, the devil pushes you to do more than you can do, even though your powers are limited, a nervousness is caused because you cannot handle it, then anxiety is caused with a little despair first and then continues…
I remember when I was a novice monk, just a while after I fell asleep, the temptation was saying, “Are you sleeping? Stand up! There are so many people who are suffering, so many who are in need”.
I was standing up and praying as much as I could. As soon as I fell asleep, the temptation said to me again: “The others suffer and you sleep? Stand up!”. I was getting up again.
Until I got to say, “Oh, I wish I had no feet! I would then be justified, since I could not kneel before the Lord to pray”.
During the Great Lent, I was exhausted but I made it through, because I was pushing myself beyond my limits.
When we feel stressful in our struggle to repentance, we have to be aware that we are not on the path to God. God is not a tyrant who wants to strangulate us.